How Much Roof Space do Solar Panels Need?
Written by
Michael Malone
Last edited
17/07/2024
Before getting started on installing a solar PV system in Ireland, you need to know just how much roof space you have available for solar panels before you start making further decisions.
A typical array of 10 solar panels on a rooftop would take up around 20m², while 12 panels might take up roughly 25m².
Smaller solar systems of around 2kWp comprising just 4 solar panels might only need around 8m², which may be the only option for those with limited roof space.
Read on as we explore the roof space needed for solar panels in more detail.
Table of Content
What size is the standard solar panel?
Standard solar panels for home installation come in two main sizes: 1m x 1.7m or 1m x 2.1m, with most having a power output of approximately 250W – 410W depending on their efficiency.
The size of these solar panels is something that will need to be taken into consideration when selecting a Solar PV system for your home.
Is your home suitable for solar panels?
The amount of solar panels required for your home depends on numerous factors including its size, how much electricity you consume, and the amount of sunlight you get.
The average household in Ireland used 4,200kWh of electricity in 2017 according to the Commission for Regulation of Utilities (CRU), which would require at least 10 solar panels to match on paper. (Source)
The majority of properties in Ireland are suitable for solar panels, as long as they aren’t installed on a north-facing roof, and that the building is not completely in shade, which will reduce their efficiency.
It’s also necessary to know how much roof space you have available for a solar PV system before making any further decisions. This should be done via a detailed site survey at an early stage of the project.
Does your roof shape allow for solar?
The shape of your roof determines how many, if any, solar panels can be installed on it. Most houses have pitched roofs, and while these are generally ideal for having solar panels angled towards the sun, they don’t always have the space.
Corners, chimneys, and uneven surfaces can inhibit the amount of solar PV panels which can be installed on the roof of a house.
See some of the examples below:
This roof does not have much space that is suitable for solar panels and the corners and projects leave little flat surface large enough.
Similarly above, the changes in roof height, projecting windows and other corners in the roof leave little unbroken space for solar panels to be installed.
The house roofs above are clearly ideal for solar, as you can see, due to the large areas of unbroken surface.
Do solar panels have to be installed on a roof?
It is most common for home solar panels to be installed on the rooftop, for convenience and easy access to the sun. But there are other options if your rooftop is unsuited to solar panels due to its shape or size.
Ground-mounted Solar Panels
More commonly seen in large solar farms, these are mounted on frames on the ground at an angle of 30° – 40° in a clear space with lots of sunlight.
Changes made to planning laws in October 2022 allow for up to 25m² of free-standing solar panels in private residences without planning permission, subject to some restrictions.
Ground-mounted panels are typically more expensive than roof-mounted solar PV systems, but you are able to choose their orientation and angle more precisely.
Solar Canopies
A solar canopy is a ground or building mounted structure which is topped with solar panels. These combine the ability to produce electricity with providing a shaded and sheltered area for people.
These outdoor structures can take the form of a fixed awning, or a type of gazebo, combining multiple functions.
Solar Carport
A solar carport is a specific type of solar canopy which is designed to cover a parking space or multiple parking spaces, providing vehicles with shelter from the elements while also generating electricity.
Factors to consider when choosing how many solar panels you need:
There are many factors to take into consideration when deciding how many solar panels to get installed on your home, based on your energy consumption and budget.
Energy Usage
The biggest thing which will affect how many solar panels you need is how much electricity you consume, and how you use it. There’s no point in getting too small a solar PV system that won’t put a dent in your electricity bill.
Location
How much sunlight you get in your area is also an important factor in what size of a system is needed. In Ireland the south and southeast get the most sunshine throughout the year, while the northwest gets the least.
If there is less sunlight in your area, more solar panels will be required to generate the same amount of electricity as elsewhere.
Solar Panel Size and Rating
Solar panels vary in their power output based on their size, the cell efficiency, and the materials which the panels are made of. Monocrystalline or Polycrystalline silicon panels, or Thin-Film Panels will all have different levels of efficiency and cost.
Your Budget
All of the above factors must be considered in light of the budget you have for installing a solar PV system on your home.
How many solar panels are needed to power a home in Ireland?
The amount of solar panels required to power a home in Ireland varies depending on the size of the home, and the amount of electricity being consumed.
Solar PV systems can potentially generate up to 70% of your electricity with a decent amount of panels and a battery system.
But installing one or two panels on their own would not be a worthwhile investment. You would still be paying most of the same costs for their installation, and a solar PV system of less than 1kWh isn’t going to massively cut your electricity bill.
An easy and informative first step in this process is to check your utility bills for your kWh energy usage as a starting point, and calculate how much electricity your home uses over a year.
FAQs
Get Your Solar Panels Quote Today
Get a consultation today to see how suitable your roof is for solar panels, and how much it would cost to have an adequate Solar PV system installed on your home.
Author:
Michael Malone
SOLAR ENERGY EDITOR
Michael Malone is Solar Energy Editor at Energy Efficiency Ireland. He is committed to highlighting the benefits of solar PV for people across the island of Ireland, and is eager to clear up some misconceptions which linger among the Irish public regarding solar energy.
Author:
Michael Malone
Solar Energy Editor
Michael Malone is Solar Energy Editor at Energy Efficiency Ireland. He is committed to highlighting the benefits of solar PV for people across the island of Ireland, and is eager to clear up some misconceptions which linger among the Irish public regarding solar energy.
How Much Roof Space do Solar Panels Need?
Written by
user
Last edited
30/10/2024
Before getting started on installing a solar PV system in Ireland, you need to know just how much roof space you have available for solar panels before you start making further decisions.
A typical array of 10 solar panels on a rooftop would take up around 20m², while 12 panels might take up roughly 25m².
Smaller solar systems of around 2kWp comprising just 4 solar panels might only need around 8m², which may be the only option for those with limited roof space.
Read on as we explore the roof space needed for solar panels in more detail.
Table of Content
What size is the standard solar panel?
Standard solar panels for home installation come in two main sizes: 1m x 1.7m or 1m x 2.1m, with most having a power output of approximately 250W – 410W depending on their efficiency.
The size of these solar panels is something that will need to be taken into consideration when selecting a Solar PV system for your home.
Is your home suitable for solar panels?
The amount of solar panels required for your home depends on numerous factors including its size, how much electricity you consume, and the amount of sunlight you get.
The average household in Ireland used 4,200kWh of electricity in 2017 according to the Commission for Regulation of Utilities (CRU), which would require at least 10 solar panels to match on paper. (Source)
The majority of properties in Ireland are suitable for solar panels, as long as they aren’t installed on a north-facing roof, and that the building is not completely in shade, which will reduce their efficiency.
It’s also necessary to know how much roof space you have available for a solar PV system before making any further decisions. This should be done via a detailed site survey at an early stage of the project.
Does your roof shape allow for solar?
The shape of your roof determines how many, if any, solar panels can be installed on it. Most houses have pitched roofs, and while these are generally ideal for having solar panels angled towards the sun, they don’t always have the space.
Corners, chimneys, and uneven surfaces can inhibit the amount of solar PV panels which can be installed on the roof of a house.
See some of the examples below:
This roof does not have much space that is suitable for solar panels and the corners and projects leave little flat surface large enough.
Similarly above, the changes in roof height, projecting windows and other corners in the roof leave little unbroken space for solar panels to be installed.
The house roofs above are clearly ideal for solar, as you can see, due to the large areas of unbroken surface.
Do solar panels have to be installed on a roof?
It is most common for home solar panels to be installed on the rooftop, for convenience and easy access to the sun. But there are other options if your rooftop is unsuited to solar panels due to its shape or size.
Ground-mounted Solar Panels
More commonly seen in large solar farms, these are mounted on frames on the ground at an angle of 30° – 40° in a clear space with lots of sunlight.
Changes made to planning laws in October 2022 allow for up to 25m² of free-standing solar panels in private residences without planning permission, subject to some restrictions.
Ground-mounted panels are typically more expensive than roof-mounted solar PV systems, but you are able to choose their orientation and angle more precisely.
Solar Canopies
A solar canopy is a ground or building mounted structure which is topped with solar panels. These combine the ability to produce electricity with providing a shaded and sheltered area for people.
These outdoor structures can take the form of a fixed awning, or a type of gazebo, combining multiple functions.
Solar Carport
A solar carport is a specific type of solar canopy which is designed to cover a parking space or multiple parking spaces, providing vehicles with shelter from the elements while also generating electricity.
Factors to consider when choosing how many solar panels you need:
There are many factors to take into consideration when deciding how many solar panels to get installed on your home, based on your energy consumption and budget.
Energy Usage
The biggest thing which will affect how many solar panels you need is how much electricity you consume, and how you use it. There’s no point in getting too small a solar PV system that won’t put a dent in your electricity bill.
Location
How much sunlight you get in your area is also an important factor in what size of a system is needed. In Ireland the south and southeast get the most sunshine throughout the year, while the northwest gets the least.
If there is less sunlight in your area, more solar panels will be required to generate the same amount of electricity as elsewhere.
Solar Panel Size and Rating
Solar panels vary in their power output based on their size, the cell efficiency, and the materials which the panels are made of. Monocrystalline or Polycrystalline silicon panels, or Thin-Film Panels will all have different levels of efficiency and cost.
Your Budget
All of the above factors must be considered in light of the budget you have for installing a solar PV system on your home.
How many solar panels are needed to power a home in Ireland?
The amount of solar panels required to power a home in Ireland varies depending on the size of the home, and the amount of electricity being consumed.
Solar PV systems can potentially generate up to 70% of your electricity with a decent amount of panels and a battery system.
But installing one or two panels on their own would not be a worthwhile investment. You would still be paying most of the same costs for their installation, and a solar PV system of less than 1kWh isn’t going to massively cut your electricity bill.
An easy and informative first step in this process is to check your utility bills for your kWh energy usage as a starting point, and calculate how much electricity your home uses over a year.
FAQs
Get Your Solar Panels Quote Today
Get a consultation today to see how suitable your roof is for solar panels, and how much it would cost to have an adequate Solar PV system installed on your home.
Author:
Michael Malone
SOLAR ENERGY EDITOR
Michael Malone is Solar Energy Editor at Energy Efficiency Ireland. He is committed to highlighting the benefits of solar PV for people across the island of Ireland, and is eager to clear up some misconceptions which linger among the Irish public regarding solar energy.
Author:
Michael Malone
Solar Energy Editor
Michael Malone is Solar Energy Editor at Energy Efficiency Ireland. He is committed to highlighting the benefits of solar PV for people across the island of Ireland, and is eager to clear up some misconceptions which linger among the Irish public regarding solar energy.
